The invention concerns in general a spot cleaning system and methodology and, in particular, is concerned with improved spot cleaning operations which provide practical method and apparatus which obviates the use of potentially harmful chlorinated solvents.
Conventional, basic technology with respect to commercial cleaning arrangements has existed for many years. However, more recently, practice of conventional techniques has been challenged by factors not previously fully appreciated. For example, commercial cleaning operations have long used devices generally referred to as a "spotting board" for spot cleaning, i.e., concentrated cleaning of a given spot or stain on a soiled garment. Generally speaking, such apparatuses have included a user workbench or workstation at which the soiled garment to be cleaned is treated. Frequently, use of such spot cleaning technique involves use of a chlorinated solvent. Generally speaking, chlorinated solvents have for many years been the industry standard for spot cleaning.
More recently, there has been considerable pressure in numerous industries to respond to environmental concerns. As worldwide studies progress, it has become recognized that certain heretofore accepted practices (including, in some instances, industry standard practices) have specific adverse environmental affects and/or contribute adversely to the environment. Chlorinated solvents are a specific example of such a situation.
Relatively recently, an international document referred to as the "Montreal Protocol" dealt with the widespread and significant problem of ozone layer depletion in the earth's atmosphere. Specifically, it is thought that chlorinated solvents are one contributing factor to ozone layer depletion or damage.
Typically speaking, chlorinated solvents are extremely fast drying, which means that their use is highly advantageous in the cleaning industry since the garment being cleaned, in effect, dries rapidly. What, in fact, is taking place is that the highly volatile chlorination in the solvents is evaporating into the atmosphere. Because generally the evaporating substance or chlorine gas is unreactive with other elements, the escaping material makes it way into areas of the earth's atmosphere so as to result in damage to the ozone layer, as referenced above.
The United States levied a federal excise tax of Eighty Dollars ($80) per 55 gallon drum of chlorinated solvents, effective as of Jan. 1, 1991. The excise tax is designed to begin shifting the cleaning industry towards elimination of chlorinated solvents. At present, the excise tax is scheduled to double (i.e.. increase to One Hundred Sixty Dollars ($160) per 55 gallon drum of chlorinated solvent) as of 1995. Other legislation is being considered due to the ever increasing recognition of the negative consequences of using chlorinated solvents. It is presently thought that chlorinated solvents may ultimately be entirely eliminated from the cleaning industry, either by regulation or due to relative expense.
Because prior industry practices relied heavily on chlorinated solvents, drying considerations have heretofore been avoided as a major problem. However, as is now more clearly understood, the drying problem associated with spot cleaning or other cleaning practices was simply being handled with a short-term solution which had highly negative long-term ramifications. Hence, the drying problem persists and a new urgency exists within the cleaning industry as to how best to practice comparable cleaning techniques (or if such is possible) without the use of (or perhaps even without the availability of) chlorinated solvents.
Prior devices, particularly pertaining to so-called "spotting boards" have made use of an upright element or arm on which a garment to be cleaned is received, and through which a degree of vacuum force is applied to the garment. Frequently, with the garment received in such a position (i.e., supported on a vacuum exhaust element), a workstation operator would work with the stain to be removed. In some instances, the above-referenced chlorinated solvents would be utilized. In other instances, it was known to make use of wet or dry steam either mixed with a solvent or without additional materials mixed therewith. As discussed, the generally pervasive use of chlorinated solvent minimized any problems with drying. However, in an arrangement such as the foregoing in which chlorinated solvents were not utilized, the existing apparatus and prevailing methodology was generally inadequate to routinely provide practical levels of drying for a wet garment being cleaned.
Examples of various prior art spotting boards are shown in the following United States patents. For example, Shoop et al. (U.S. Pat. No. 2,602,315) illustrates a combination device including a spotting board 1 and connections for a steam inlet (element 5c) and a vacuum line (element 6). The operator controls the amount of moisture in the steam as desired which is being issued from a spotting gun 20. The vacuum is drawn through a screen 1b and a vacuum channel 2 towards a condenser element 5.
In another prior art example of a garment spotting machine, Glover, Jr. (U.S. Pat. No. 2,707,874), illustrates use of a steam input (reference 58), which is subjected to a separator, so that "dry" and "wet" steam is made available. Two separate spray guns are then used, with a spotting gun 72 used with the steam and a water spray gun 94 used to discharge cold water onto a spotted area.
Richterkessing (U.S. Pat. No. 2,657,566) discloses another example of a prior art spotting board, which externally receives both compressed air and steam. Yet another prior art device which constitutes a spotting board which receives external inputs is referred to as a "Cissel" board manufactured by the Cissel Board Company of St. Louis, Mo. Such an arrangement requires an external vacuum to be hooked thereto, and steam to be brought in from an external line, typically from a full-sized steam boiler located at the commercial plant at which the board is being used. With such an arrangement, the external vacuum achieved may typically be no more than approximately 20 to 25 inches of mercury of static vacuum pressure. Such relatively low level of vacuum force would ordinarily be a sufficient amount of vacuum for drying purposes only whenever chlorinated solvents are utilized, as discussed above. Generally, such vacuum force would be inadequate if a garment being cleaned were wet from a water-based source.
Examples of other prior art devices making use of various features, such as external vacuum or steam inputs, are shown in the following U.S. patents.
______________________________________ U.S. PAT. NO. INVENTOR(S) ISSUE DATE ______________________________________ 4,434,012 ECKERT ET AL. FEBRUARY 28, 1984 3,427,831 FRAUENDORK FEBRUARY 18, 1969 3,320,780 FRAHM MAY 23, 1967 3,030,792 BADER APRIL 24, 1962 2,434,404 GOODWIN JANUARY 13, 1948 2,295,718 DAHLBERG SEPTEMBER 15, 1942 2,254,691 MACLELLAND, JR. SEPTEMBER 2, 1941 ______________________________________
Another aspect of changing circumstances in the cleaning industry is that locally available full-sized steam boilers are diminishing in number, which can tend to further increase the desire to make use of chlorinated solvents and/or other approaches which minimize drying problems. Likewise, centralized vacuum mechanisms tend to be of a relatively low vacuum level as referenced above, which is further reason for making use of virtually self-drying solvents such as chlorinated solvents. Typically larger bore hose connections or the like, such as connecting a vacuum line to the above-referenced "Cissel" board, is another reason for resultingly relatively low vacuum forces at the spotting board.